Shaving unit for safety razor

ABSTRACT

The specific disclosure provides a shaving unit having two flexible double edge razor blades with the cutting edges of the top blade being set back a slight distance from the cutting edges of the bottom blade. The blades are vertically separated by a spacer, and an elongated aperture extends through the blades and the spacer for locating the shaving unit in a double edge safety razor. Means are provided between the aperture and the cutting edges to one side of the aperture for permanently connecting the top blade to the spacer, and means are provided between the aperture and the cutting edges to the other side of the aperture for permanently connecting the bottom blade to the spacer.

United States Patent [1 1 Ferraro June 17, 1975 1 SHAVING UNIT FORSAFETY RAZOR [75] Inventor:

22 Filed: Dee.,13, 1974 21 App]. No.: 532,429

Frank A. Ferraro, Trumbull, Conn.

[52] US. Cl 30/134658; 30/50 [51] Int. Cl. B26B 21/54; B2613 21/22 [58]Field of Search 30/50, 34657, 346.58,

30/346.59; 76/DIG. 6

[56] References Cited UNITED STATES PATENTS 3,262,206 7/1966 Tomek30/346.59

FOREIGN PATENTS OR APPLICATIONS 1,103,671 11/1955 France 30/346.58

Primary Examiner-Al Lawrence Smith Assistant Examiner-Gary L. SmithAttorney, Agent, or Firm-James F. Powers, Jr.; Albert H. Graddis [5 7]ABSTRACT The specific disclosure provides a shaving unit having twoflexible double edge razor blades with the cutting edges of the topblade being setback a slight distance from the cutting edges of thebottom blade. The blades are vertically separated by a spacer, and anelongated aperture extends through the blades and the spacer forlocating the shaving unit in a double edge safety razor. Means areprovided between the aperture and the cutting edges to one side of theaperture for permanently connecting the top blade to the spacer, andmeans are provided between the aperture and the cutting edges to theother side of the aperture for permanently connecting the bottom bladeto the spacer.

10 Claims, 3 Drawing Figures 1' SHAVING UNIT FOR SAFETY RAZOR BACKGROUNDOF THE INVENTION 1. Field of the Invention The present invention relatesto shaving units having. a plurality of cutting edges for use in asafety razor. More particularly, the present invention relates to safetyrazor shaving units having a plurality of double cutting edge membersbonded together.

2. Description of the Prior Art Double edge safety razors are well-knownin the art,

I and are in many forms. For example, US. Pat. Nos.

3,293,745, 3,466,746 and 3,708,879 disclose a razor having sectionalcaps, an adjustable razor and a razor having a hinged cap, respectively.Such razors act to I clamp a thin, flexible couble edge razor blade inthe blade are set back a slight distance from the cutting edges of thebottom blade to provide tandemly arranged cutting edges on eachside ofthe shaving unit. U.K. Pat. No. 772,532 contemplates welding the bladesand spacer together, and, at Page 3, lines 98-100, specifically teacheswelding the spacer near its elongated ends.

Commercially available flexible steel double edge razor blades having anelongated central slot parallel to the cutting edges are arcuatelyflexed at tab portions at each end of the slot when firmly seated indouble edge razors having manually operatedmechani sms for opening andclosing the cap portion. However, as shown in FIG.4 of US. Pat. No.3,708,879, the portions of the razor blades between the slot and thecutting edges are at least substantially flat.

Weldingrnetal increases grain size of the metal about the weld, and thecorrosion rate about the'weld is high. When double edge razor blades arewelded together at the tab portions, and the tab portions are thereafterarcuately bent in a razor as specifically taught in U.K. Pat. NO.772,532, a danger of stress-corrosion cracking is raised;Stress-corrosion cracking is failure by cracking under combinedcorrosion and applied and /or residual stress.

SUMMARY OF THE INVENTION In accordance with the present invention, thereis provided a shaving unit for a double edge safety razor comprising afirst flexible member having a pair of opposite cutting edge sides. Asecond flexible member also having a pair of opposite cutting edge sidesis located above the first member with the cutting edges of the secondmember being set back a slight distance from the cutting edges of thefirst member. Means are A shaving unit constructed in accordance withthe present invention minimizes the stress-corrosion cracking problem bybonding the components of the shaving unit at surfaces which are atleast substantially flat when the unit isseated in the razor.

Further, the amount offorce needed to seat theunit in the razor is alsominimized by each one of the first and second members being connected toan opposite side of the spacing means. This manner of connecting thecomponents together permits a slight cutting edgesto-cutting edgesrelative motion between the compo nents as the unit is seated in therazor.

v BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF SPECIFIC EMBODIMENTSWith reference to FIGS. 1 and 2, one representative embodiment of thepresent invention has first -and'second'members 82, 81 in the form ofdouble cutting'e'dge razor-blades, and means in the form of a spacerelement 80 for vertically spacing the second me'mber 81 from the firstmember 82. The top blade 81 and the spacer element 80 are permanentlyconnected together by two welds 76'diagrammatically represented bydashed circles on one side 79 of transversely elongated apertures 83, 84formed in the spacer element 80 and the top blade 81. The bottom blade82 and the spacer element 80 are permanently connected together by twowelds 77 diagrammatically representedbydashed circles on the other side78 of transversely elongated apertures 83, 85 formed in the spacerelement 80 and the bottom blade 82.

The top blade 8115 but away at 96, 97 above the welds 77, and the bottomblade 82 is similarly cut away at 98, 99 below the welds 76 to permitspot welding of the blades 81, 82 to opposite sides of 'the spacerelement 80. a

As clearly shown in FIG. 2, the cutting edges 88; 89 of the top blade 81are set back a slight distance from the cutting edge 90, 91 of thebottom blade 82. The cutting edges 88, 89 on opposite sides of the topblade are parallel to the cutting edges 90, 91 on opposite sides of thebottom blade 82. The spacer element 80 has a pair of blunt surfaces 86,87 set back a slight distance from the cutting edges 88, 89 of the topblade 81. The apertures 83-85 extend between end tab portions 72, 73;70, 71; 74, of the spacer element and the blades 81, 82.

FIG. 3 shows the shaving unit seated and clamped in a double edge safetyrazor having a center-bar and stem assembly 40. The center-bar and stemassembly 40 is fitted through the apertures 83-85 to locate the shavingunit in the razor. A pair of sectional caps 41, 42 act to bias theshaving unit on a blade seat with the cutting edges of the blades 81, 82tandemly arranged with respect to guard bar surfaces 44, 45 formed onthe outer ends of the blade seat. FIG. 3 also shows the shaving unitportions 78, 79 between the tabs 70-75 in a flat state. However, the tabportions 70-75 are arcuately bent (not shown).

The end tab portions 72, 73; 70, 71; 74, 75 have cut out portions 30,31, and the blades 81, 82 and the composed of thin martensitic stainlesssteel commonly used for razor blades, or of any other flexible materialsuitable for double edge razor blades. The thickness of the blades 81,82 and of the spacer 80 can be 0.0039 inches. The distance between thecutting edges of the top blade 81 can suitably be 0.832 inches whenthe'distance between the cutting edges of the bottom blade is 0.870inches. The distance betweenthe blunt surfaces 86, 87 of the spacerelement 80 can be 0.780 inches.

The shaving unit can be welded anywhere on the flat shaving unitportions, 78, 79 between the tabs 71, 73, 75; 70, 72, 74, butsufficiently inwardly of the top blade cutting edges 88, 89 to avoidadversely affecting the' cutting edges 88, 89. However, as noted abovethe top blade 81 is preferable perforated above the welds con- I nectingthe spacer element 80 to the bottom blade 82,

and the bottom blade 82 is perforated below the welds connecting the topblade 81 to the spacer elements. Such perforations permit the blades 81,82 and the spacer element 80 to be stacked as shown in FIG. 2,

, and'the welds applied in a single process step.

The components of shaving units can be bonded to- I gether by spot,'-projection, arc, laser or other welding techniques, and more thana twowelds can be provided to each side of the aperture. The flat shavingunit portions 78, 79 alternatively can be bonded to opposite sides ofthe spacer by adhesives. Further, the spacer can be formed of a plasticmaterial.

The embodiment shown in the figures has symmetrically beveledsurfaces-forming the cutting edges of the blades 81, 82. However, it iscontemplated that the beveled cutting edge surfaces of :one or both ofthe blades 81, 82 canbe asymmetrically ground to increase the verticaldistance between the cutting edges of the l 4 a. a first flexible memberincluding a pair of transversely extending opposite sides, each one ofthe first member opposite sides having a cutting edge; b. a secondflexible member including a pair of transversely extending oppositesides, each one of the second member opposite sides having a cuttingedge, said second member being located above said first member with thecutting edges of said second member being positioned upwardly andinwardly of the cutting edges of said first member;

" c. flexible means between said first member and said second member forspacing said second member from said first member;

d. a transversely elongated aperture extending through said firstmember, said spacing means and said second member between the cuttingedges of said first member and said second member for 10- cating saidshaving unit in said safety razor;

e. first means between said aperture and the cutting edges to one sideonly of said aperture for permanently connecting said first member tosaid spacing means; and a f. second means between said aperture and thecutting edges to the other side only of said aperture for permanentlyconnecting said second member to said spacing means.

2. The shaving unit of claim 1 wherein the cutting edges of said firstmember and said second member are parallel.

3. The shaving unit of claim 2 wherein said firstand second members aremetallic members. I I

4. The shaving unit of claim 3 wherein said spacing means is a metalliccomponent. I I

5. The shaving unit of claim 4 wherein said first and second-connectingmeans each comprises. a plurality of spot welds. v t

6. The shaving unit of claim 4 wherein said first. and second membersare double cuttinge dge safety razor blades.

7. The shaving unit of claim 6 wherein said first and second connectingmeans each comprises a plurality of spot welds. g

8. The shaving unit of claim 1 wherein said first and second memberseach further include a pair of spaced end tabs extending outwardly fromopposite ends thereof.

9. The shaving unit of claim 1 further comprising a plurality ofperforations in said spacing means between said aperture and the cuttingedges to each side of said aperture.

10. The shaving unit of claim 9 further comprising a plurality ofperforations in said first and second members between said aperture andthe cutting edges to each side of said aperture.

1. A shaving unit for a double edge safety razor, said shaving unitcomprising: a. a first flexible member including a pair of transverselyextending opposite sides, each one of the first member opposite sideshaving a cutting edge; b. a second flexible member including a pair oftransversely extending opposite sides, each one of the second memberopposite sides having a cutting edge, said second member being locatedabove said first member with the cutting edges of said second memberbeing positioned upwardly and inwardly of the cutting edges of saidfirst member; c. flexible means between said first member and saidsecond member for spacing said second member from said first member; d.a transversely elongated aperture extending through said first member,said spacing means and said second member between the cutting edges ofsaid first member and said second member for locating said shaving unitin said safety razor; e. first means between said aperture and thecutting edges to one side only of said aperture for permanentlyconnecting said first member to said spacing means; and f. second meansbetween said aperture and the cutting edges to the other side only ofsaid aperture for permanently connecting said second member to saidspacing means.
 2. The shaving unit of claim 1 wherein the cutting edgesof said first member and said second member are parallel.
 3. The shavingunit of claim 2 wherein said first and second members are metallicmembers.
 4. The shaving unit of claim 3 wherein said spacing Means is ametallic component.
 5. The shaving unit of claim 4 wherein said firstand second connecting means each comprises a plurality of spot welds. 6.The shaving unit of claim 4 wherein said first and second members aredouble cutting edge safety razor blades.
 7. The shaving unit of claim 6wherein said first and second connecting means each comprises aplurality of spot welds.
 8. The shaving unit of claim 1 wherein saidfirst and second members each further include a pair of spaced end tabsextending outwardly from opposite ends thereof.
 9. The shaving unit ofclaim 1 further comprising a plurality of perforations in said spacingmeans between said aperture and the cutting edges to each side of saidaperture.
 10. The shaving unit of claim 9 further comprising a pluralityof perforations in said first and second members between said apertureand the cutting edges to each side of said aperture.